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Finding the Fourth Proportional to 68.78, 103.77 and 65.05

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Solution

The fourth proportional to 68.78, 103.77 and 65.05 is: 98.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.78 : 103.77 = 65.05 : x
  2. Step 2: Convert to fraction form
    68.78/103.77 = 65.05/x
  3. Step 3: Cross multiply
    68.78x = 103.77 × 65.05
  4. Step 4: Simplify right side
    68.78x = 6,749.98
  5. Step 5: Solve for x
    x = 6,749.98/68.78
  6. Step 6: Final answer
    x = 98.14

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.